Landing gear for semitrailers



Aug. 10, 1937. c. H. LAND LANDING GEAR FOR SEMITRAILERS 4 Sheet-Sheet 1 Filed Aug. 20, 1956 A llorney Aug. 10, 1937. c. H. LAND LANDING GEAR FOR SEMITRAILERS Filed Aug. 20, 1936 4 Sheets-Sheet 2 on w m w m I :1} .m A i l 14 m y 1 m 1 M \\m ||.|I. f hm MN I Mm W m I. j 5. mm m Aug. 10, 1937. c. H. LAND LANDING GEAR FOR SEMITRAILERS Filed Aug. 20, 1956 4 Sheets-Sheet 3 Z Inventor fifziww Altorney 4 Sheets-Sheet 4 C. H. LAND Filed Aug. 20, 1936 LANDING GEAR FOR SEMITRAILERS LL IllllIl/I/l/Ill/I/I/ll/ll/l/I/ Aug. 10, 1937.

3nvcnto1 444 Z44 0 attorney Patented Aug. 10, 1937 UITE STATES LANDING GEAR FOR SEMITRAILERS Charles H. Land, Detroit, Mich., assignor of onehalf to William H. Wilson, Detroit, Mich.

Application August 20, 1936, Serial No. 96,941

'7 Claims.

'10 upon which there is 'no draft in transit.

Another object is to provide a coupling element on the tractor which automatically engages the head on the actuating bar at the beginning of the coupling operation and is released near the end of the uncoupling operation.

In the accompanying drawings:

Figure 1 is a plan View of an apparatus embodying my invention partly broken away.

Figure 2 is a sectional elevation of the same '20 substantially on the line 22, of Figure 1.

. Figure 3 is a detail elevation looking from the locality, and in the direction, of the arrows 3-3, Figure 1,the back portion of the casing being removed;-the shaft of the pawl being -25 shown in section.

Figure 4 is a detail section on the broken line 4Ii, Figure 3.

Figure 5 is a detail elevation similar to Figure 3, showing the parts in diiferent relative positions.

30 Figure 6 is a detail elevation taken as indicated by the broken line 6-4: and arrows, Figure 1.

Figure 7 is a plan of a portion of the front part of the tractor-trailer, showing a modified con- 35 struction.

Figure 8 is a detail section on or about line 8--8, Figure 7.

Figure 9 is a detail sectional view showing the head on the landing-gear actuating bar, and ad- 40 jacent casting, drawn to a larger scale than in Figure 1.

Figure 10 is an enlarged view of the forward portion of the trailer,shown in Figure 2, coupled to the tractor.

45 In the drawings:

A denotes a tractor with ramp-plate I, secured to its frame. Numeral 2 indicates a pedestal bolted to the side sills of the tractor and supporting a rocking fifth-wheel 3. The numeral 4 50 is the king-pin-to which the trailer is lockedprojecting upwardly from the fifth wheel 3, and provided with a coaxial bore. Numeral 5 indicates a flanged pin having a downwardly extending shank, adapted to fit and reciprocate in the 55 bore of the king-pin 4. A bell-crank l is linked by pin 6 to the lower end of the shank of the pin 5. Said bell-crank is pivoted by a pin 8, to lug castings 99. A spring l attached to lugs H and I2, keeps the flanged pin in its upper position. Its motion is limited by the lug l3. 5 Numeral M indicates a yoke pinned to the lower arm of the bell-crank lever l. A rod 15 extends to the cab for operating said lever to depress the flanged pin 5.

B designates a trailer with the usual side sills [6-16 and cross members l'lll. l8-l8 indicate skid castings bolted to the front cross mem bers and equipped with rollers l9-I 9. Said castings form a wide-flaring approach to the throat 22 of the trailer. 20-20 denote wear plates spaced apart at the center and riveted to the under side of the sills l6 and cross members I1. 2l2| denote L-shaped guides, welded to the upper side of said wear plates to form a throat 22, to guide and maintain the king-bolt in its proper position, during the coupling and uncoupling of the tractor to the trailer. 23 indicates a tubular landing-gear-actuating bar extending longitudinally of the trailer frame. At the forward end of the bar 23, a head casting 24 25 is pinned.

On the under side of said casting, arc-shaped flanges 25 extend downwardly for a part of the circumference to form a pocket for the flanged head of the king-pin 4. 3O

Numeral 25 denotes a roller attached to the upper side of the head casting 24, which contacts the guide 21.

Numeral 28 indicates a casting above the throat and across it, having a downwardly inclined lower face and a straight lip 29, extending rearwardly. Said casting depresses the pin 5, so that its flanged head may register with the head 24, and engage in the pocket formed by the arced flanges 25-25. The numeral 30 denotes a head adapted to travel longitudinally in guide channels 3I-3l fastened between cross-members Il-l'l. Both ends of this head are bored, one to receive the collar 32, and the other to receive the actuating bar 23. The collar 32 is pinned to the bar 23, 5 and is flanged to limit its backward slide in the head 30. Numeral 33 denotes a collar pinned to the rear end of the actuating bar 23, which limits the forward movement of said bar relative to the head 39. Numeral 34 indicates a coil spring, 59 under compression, surrounding the bar 23, between the two upright ends of the head 30. One end of said coil-spring bears on the rear upright 01" said head and the other end of the spring bears against the slidable collar 32, pinned to the actuating bar 23. Numeral 35 denotes a pawl sleeved and adapted to oscillate upon a shouldered pin on casting 31, riveted to the side of one of the channel guides 3l--3l. The lower arm of said pawl contacts an angular face 38 on one side of the slidable head 33 when said head is forward. An arm 39 extends upwardly from the pawl 5. A lug 46 projects horizontally from the rear head collar 33, in position to engage the arm 39 when the head 39, is at the end of its forward travel. A spring il tends to turn the pawl to engage the surface 38. The leg members l'Z-QZ are pivoted by pins 43-43 to castings 44-44 riveted to the outside of the sills !6l6. At the lower ends of said leg members are castings 45,

clamped to the axle it, which carries the wheels ll-fil. Said leg members are also tied together by a cross bar 48 which is fastened to castings, secured to the leg members EL-42.

The leg arms 49-49 are pivotally connected to the bar 48 at their lower ends, and at their upper ends to the slidable head 30.

In the modified construction of Figures '7 and 8, the head 24 is shown as slotted at 24a, and a 25 casting 28a, is substituted for the casting 28, and

having a central flange 28b, extending rearwardly at its center having a downwardly inclined lower edge 280 for depressing the flanged pin 5. The rear end of the flange 2% may extend into the 30 slot 2%; and at this point its lower edge turns upward as shown at 28d so as to permit the pin 5 to rise gradually to engage between the arced flanges 2525, and when the tractor is withdrawn the portion of the lower edge of the flange 28b engages the head of the pin 5 and depresses it so that it shall clear the forward flange 25.

The operation of the above described apparatus is as follows:

The drawings show the landing gear with its parts in the position at which they are shown to be actuated in the coupling of the tractor or trailer, or in the position they take when the tractor is about to be separated from the trailer. In the latter case the flanged pin 5, must be manually withdrawn from the pocket in the head 23 before the tractor is completely detached from the trailer. This is accomplished by a pull eX- erted on rod l5, which swings the bell-crank lever 'l', and depresses the flanged head of the pin 5, below the lip 29, of the casting 28. a

When the tractor is coupled to the trailer the parking brakes of the trailer are set. The kingpin t-S has been guided into the throat 712 of the trailer as the trailer rises over the tractor flfth-wheel. The flanged pin 5, having been depressed automatically by the incline of the casting 28 and its lip 29, jumps into the pocket on the lower side of the head 25. This is essential as there must be no motion given to the actuating bar 23 before these two members register.

As the tractor backs, the flange of the pin 5 rides over the upper edges of the guide 2l2l, and the king-pin 4, is held closely between said guides.

The landing gear is locked by the pawl 35 engaging the surface 38, of the cross-head 3 5 as shown in Figure 3. Before the legs 42 start to swing upward toward the position indicated by broken lines in Figure 2, the landing gear must be unlocked. The backward thrust of the actuating bar 23, to which the slidable head 32 is fixed, compresses the coil spring 34, and carries the collar 33 with its projecting lug 40 backward. Said lug engages the upper arm 39 of the pawl 35,. and turns the pawl out of engagement with the surface 38, thus releasing the head38. The bar 23 is carried backward by the flanged pin 5, as the king-pin 6 moves towards its engaging position, and forces the head backward, thus drawing the legs 22 to their disengaged position as shown by broken lines in Figure 2. Said position is reached when the jaws 5l5l look around the king-pin 4.

On the uncoupling stroke the spring 34 will bring the collar 33, in contact with the rear portion of the head 33. The arm 35 of the pawl will be held tripped (Figure 5) by the upper edge of the guide M of the head until the surface 38 has been reached when it will be sprung into locked engagement therewith. The upper arm 39 of the pawl 35 will be in contact with the lug 40. The landing gear cannot be folded until heavy pressure is exerted upon the actuating bar during the coupling stroke.

It is to be noted there is no transit draft upon the bar 23.

In the coupling operation the flanged head of the pin 5 rides upon the upper edges of the guides 24-2! and cannot be depressed during the coupling stroke.

The parking brakes are shown set and the jaw lock released and the coupling and engagement is elfected as shown in an accompanying application for Letters Patent on the brake construction shown. The brakes are set and securely held by the pawl and ratchet herein shown and described in said accompanying application. At the end of the coupling operation the pin 5 strikes against said pawl and frees the same from the ratchet freeing the brakes.

What I claim is:-

1. In a tractor-trailer the combination of alongitudinally reciprocating bar on the trailer, adapted to actuate the landing gear, having a cavity therein; and a tractor having a king-pin and a part adapted to reciprocate in said kingpin and protruding therefrom to engage in said cavity, on the coupling operation.

2. In a tractor-trailer the combination of a longitudinally reciprocating bar on the trailer, adapted to actuate the landing gear having a cavity therein, one wall of said cavity being slotted; and a tractor having a spring-actuated part adapted to engage in said cavity, said trailer having a flange adapted to enter said slot, said flange having a slanting portion adapted to depress said spring actuated part to guide it into engagement in said cavity, and an oppositely slanting portion adapted to enter said slot to depress said spring-pressed part to disengage it from said cavity during. uncoupling and to permit the gradual engagement of the same during coupling.

3. In a tractor-trailer the combination of a longitudinally reciprocating bar on the trailer, adapted to actuate the landing gear, having a cavity therein; and a tractor having a king-pin and a part adapted to reciprocate in said kingpin, and protruding therefrom to engage in said cavity on the coupling operation, said trailer having a guide for said king-pin, said protruding part being adapted to engage the walls of said guide to hold it in engagement with said cavity until the end of the coupling stroke.

4. In a tractor-trailer the combination of a longitudinally reciprocating bar on the trailer; a longitudinally reciprocating cross-head; a spring on said bar interposed between the spaced walls of the head; a pawl on a fixed pivot adapted to hold said head in its initial position, said bar 20 tractor king-pin-part;

being provided with a lug adapted to contact said pawl and release the same, when the spring is contracted by the relative movement of the bar and cross-head; and a landing gear connected with said cross-head.

5. In a combined vehicle of the character described, the combination of a tractor; a depressible king-pin-part on said tractor; a trailer; a reciprocating bar connected to a landing gear on the trailer, adapted. to be engaged by said pin; a cam on said trailer adapted to depress and release said pin to effect the engagement of said pin with said bar on the coupling of the tractor and trailer.

6. In a combined vehicle of the character described, the combination of a tractor; a depressible king-pin-part on said tractor; a trailer; a reciprocating bar connected to a landing gear on said trailer, adapted to be engaged by said a double cam on asid trailer adapted to depress and release said kingpin-part to effect the engagement of said pin with the front end of the bar, connected with said landing gear on the coupling of the tractor and trailer, and to effect the disengagement of said pin with the bar connected with said landing gear on the uncoupling of the same.

'7. A combined vehicle of the character described comprising in combination a tractor having a king pin; a depressible pin mounted in the king pin; a trailer; a landing gear mounted on the trailer; a longitudinal bar connected to the landing gear adapted to move back and forth upon coupling and uncoupling of the tractor and trailer; a head on said longitudinal bar, adapted to engage said depressible pin mounted in the king-pin, at the beginning of the coupling operation; and a part at the forward end of the trailer adapted to disengage the head of the longitudinal bar from the projected portion of the depressible pin at the end of the uncoupling stroke.

CHARLES H. LAND. 

